Continuous casting apparatus



June 12, 1956 M. J. FEY ETAL couwmuous CASTING APPARATUS 4 Sheets-Sheet1 Filed Jan. 22, 1952 INE'N June 12, 1956 M. J. FEY ETAL CONTINUOUSCASTING APPARATUS 4 Sheets-Sheet 2 Filed Jan. 22, 1952 June 12, 1956 M.J. FEY ETAL 2,749,534

CONTINUOUS CASTING APPARATUS Filed Jan. 22, 1952 4 Sheets-Sheet 3IIIIIIHIIIIIIIIHIHIH Inn mum

m ll l IiHlillllllUlHH] O0 INVENTORS.

36 J WXM M June 12, 1956 M. J. FEY ET AL CONTINUOUS CASTING APPARATUS 4Sheets-Sheet 4 Filed Jan. 22, 1952 United States Patent Ofilice PatentedJune 12, 1956 CONTINUOUS CASTING APPARATUS Mathias J. Fey and Howard M.Ray, Davenport, Iowa, as-

signors to Nicllois Wire & Aluminum Co., Davenport, Iowa, a corporationof Missouri Application January 22, 1952, Serial No. 267,638

2 Claims. (Cl. 22-57.4)

The present invention relates to apparatus for casting metal to producea continuous cast metal rod or strip.

Machines and apparatus for continuously casting molten metal to form acontinuous cast metal rod are generally known. Essentially, suchmachines are arranged to provide a movable casting groove or mold inwhich molten metal is continuously poured to be solidified and strippedtherefrom.

Difiicuities have been encountered in the art in devising a machine thatwill meet with any substantial degree of commercial success for a numberof reasons, outstanding among which have been the difiiculties ofproviding apparatus to operate in truly continuous fashion and toproduce a continuous cast metal rod of uniform high quality. One problemto be overcome in machines of this type is the tendency of the castmetal rod formed thereby to have numerous surface cracks and many voidsand whorls in the cast section which considerably lower the quality ofthe cast rod. It is believed that the surface cracks and the interiorvoids are caused by the diificulty in properly controlling the feed ofthe molten metal to the casting groove and in rapidly cooling orsolidifying the the molten metal and stripping the cast metal from thecasting groove. The continuous operation of the casting machine has beenhampered among other things by the difficulties in supplying the pouringladle of the machine with a continuous feed of molten metal overcomparatively long periods of time which, from a practical standpoint,has been difiicult to do with a reasonable number of machine operatorsand attendants.

It is an important object of the present invention to provide animproved apparatus for casting molten metal which will operatecontinuously over long periods of time to produce a continuous castmetal rod of uniform high quality.

Another object of the invention is to provide an improved form ofcontinuous metal casting machine arranged to rapidly and thoroughly coolthe molten metal to form a solidified continuous metal rod of goodquality and homogeneous cross section.

Another feature of the invention is the provision in a continuous metalcasting machine, of a hollow rotatable casting drum having an externalperipheral casting groove and a large interior enclosure for the flow ofcooling liquid therethrough, together with a cooling system having anarrangement of liquid intake and drain pipes enabling substantially theentire volume of the hollow enclosure of the drum to be continuouslyfilled with a moving current of a large volume of cooling liquid.

Further objects, features, and the attending advantages of the presentinvention will be apparent with reference to the following specificationand drawings, in which:

Figure l is a perspective view of the continuous casting apparatus ofthe invention, showing the general layout of casting machine and metalmelting and holding furnaces;

Figure 2 is a perspective elevation to show the details of the castingmachine;

Figure 3 is a fragmentary section through the rotatable casting drum toshow details of the cooling system;

Figure 4 is a fragmentary top plan view showing the metal pouring ladlefor the casting machine;

Figure 5 is a longitudinal section through the pouring ladle taken alongthe lines 5'5 of Fig. 4;

Figure 6 is a side elevation of the casting machine to show theadjustable features of the machine; and

Figure 7 is a fragmentary view, partly in section, of the endless bandcleaning element.

Referring to Figure 1 of the drawings for a more detailed description ofthe general layout of the continuous casting apparatus of the invention,the continuous casting machine is generally indicated at 10. A pluralityof metal melting furnaces 11, 12, and a holding or storing furnace 13are positioned in a novel arrangement in combination with the continuouscasting machine 10 to assure a flexibly controlled, continuous supply ofmolten metal to be cast. The particular layout arrangement of furnacesas shown in Figure l is somewhat out of proportion for purposes ofillustration, and it should be understood that the invention is notlimited to the exact arrangement shown. Each of the furnaces 11, 12, and13 may be of any suitable type such as the electric induction type, andis mounted on a framework by means of which the furnaces may becontrollably tilted to cause molten metal to flow from the furnacesthrough the respective molten metal outlets 15, 16, and 17 and into therespective refractory lined conduits 18, 19, and 20. The furnaces 11 and12 are arranged to be supplied with metal billets to be melted while thefurnace 13 is intended to function as a holding pot to receive moltenmetal from either of the metal melting furnaces 11 and 12 and store suchmetal for controlled feeding through the refractory conduit 24) to theheated metal pouring ladle 21 of the continuous casting machine 10. Withsuch an arrangement, the flexiblity is such that either of the furnaces11 and 12 may be shut down for repairs or may contain different metals,if, for example, a metallic alloy is to be cast. The metal meltingfurnaces 11 and 12 are mounted on raised platforms 22 and 23,respectively, in a position to be elevated above the holding pot orfurnace 13 so that molten metal from the furnaces 11 and 12 will fiow bygravity through the conduits 18 and 19 to the holding furnace 13.Similarly the holding furnace 13 is positioned to be elevated above themetal pouring ladle 21 so that molten metal will flow by gravity throughthe conduit 26 when the holding furnace 13 is tilted. The furnaces 11,12 and 13 are tilted to individually control the flow of metal therefromby means of suitable servo-mechanisms (not shown). The control buttons25, 26 and 27, located on the casting machine 10 at the castingoperators station are provided to remotely control the tiltingoperations of the respective furnaces. Thus the casting machine operatormay easily control the how of molten metal from the metal meltingfurnaces, and the molten metal holding furnace, to the pouring ladle ofthe continuous casting machine.

The room layout of the casting machine 10 and furnaces 11-13 asgenerally shown by Fig. l is compact and efficient and may be arrangedin a substantially square floor space of about sixteen feet on eachside. When casting aluminum rod, for example, to produce rolled aluminumwire, a rolling machine may be positioned to receive the cast roddirectly as it emerges from the casting machine. In one commercialapplication of the invention the rolling mill having a length of about28 feet is positioned approximately 20 feet from the casting machinegiving a total length of floor space from melting furnaces to the outputend of the rolling mill of only about to feet.

Molten metal from the pouring ladle 21 is fed by the pouring spout 30into the peripheral casting groove of the hollow rotatable casting drum31. The hollow casting drum 31 is adapted to be continuously filled witha moving current of cooling liquid. The casting drum 31 is rotated bysuitable power transmission means enclosed within the base housing 32and is provided with a variable speed control means that is controlledby the hand wheel 33. Details of the transmission are not shown and itmay take various forms, preferably having an electric motor drive. Thepush button switch 34 controls the application of power to the electricmotor of the power transmission for rotating the casting drum. A pan 35is fastened to the base portion 32 of the machine and is adapted tocontain a quantity of continuously moving cooling liquid about the lowerhalf of the rotatable casting drum 31, thus providing a further sourceof cooling liquid to aid in rapidly solidifying the molten metal in thecasting groove. The arrangement of the cooling liquid inlet and outletpipes 39a and 39b respectively, for the pan 35, is most clearly shown inFig. 2 of the drawings.

An endless metal band 36 is looped about a portion of the periphery ofthe casting drum 31 and a portion of the periphery of an idler wheel 37whose axis of rotation is spaced horizontally and vertically from theaxis of rotation of the casting drum. The axle mechanism of the idlerwheel 37 is provided with an eccentric bearing portion (not shown indetail) which, in response to the weighted arm 38, causes the idlerwheel to tension the endless band 36 against the periphery of both theidler wheel 37 and the casting drum 31. The weight 38 is movable on itssupporting arm to provide a degree of control for the tension of theendless band 36. The endless band 36 engages a portion of the peripheryof the casting drum 31 to form a closure wall for the casting groove ofthe casting drum that is movable coincidentally with the rotation of thecasting drum 31. In view of the simple loop configuration of the endlessband, the band is long wearing and may be formed of various thicknessesand of different materials suitable for different metals to be cast. Insuch manner a movable casting mold in which molten metal may becontinuously solidified to form a continuous cast metal rod is provided.Cast metal rod is shown at 40 and it will be seen that it is strippedfrom the casting drum 31 near the point of departure of the endless band36 from the casting drum 31 and is lopped over the casting machine witha general curvature in the direction of rotation of the casting drum.The casting drum 31 is arranged to rotate in a clockwise direction asshown by the arrow on Fig. l.

The cast metal rod 40, as it is stripped from the casting drum 31, isguided in its passage over the casting drum and to one side of theendless band 36 by the guide member 41 which consists of a generallytriangular shaped frame member depending from the axis of idler wheel3'7. An additional guide member 42 is mounted on the base frame 32 ofthe machine and is provided with a coil spring 43 to cause the guidemember to engage the outer surface of the cast metal rod 40 andconstrain the cast metal rod towards the axis of the casting drum 31,immediately as the cast rod is stripped from the casting groove. Thusany bowing action which may be present in the extended length of castmetal rod, which has been stripped from the machine, and which bowingaction would tend to straighten the rod immediately as it is strippedfrom the drum, is resisted by the pressure of the guide member 42 sothat the formation of surface cracks on the cast rod is minimized.

Many of the elements of the machine which have been described inconnection with Figure 1 of the drawing are shown in greater detail inFigures 2 and 6 of the drawings, to which reference is now made for afurther description of certain details. The idler wheel 37 is rotatablysupported at the upper end of the generally U-shaped frame member 50.The U-shaped frame member 50 is pivotally journalled at 51 about the hubor axis of the rotatable casting drum 31. A rotatable hand wheel 52 iskeyed to a threaded shaft 53 that is supported in the threaded bushing54. The threaded bushing 54 is fastened to the base frame 32 of themachine. The shaft 53 is pivotally connected at 55 to the other end ofthe U-shaped frame 50. By rotating the hand wheel 52, the tilt of theframe 50 and thus the entire machine may be adjusted to predetermine thedesired angle to the vertical for the straight extending portions of theendless band 36. The specific details of the connections for the shaft53 do not form a part of the present invention and are therefore notdescribed. A coil spring 56 is provided to counterbalance the weight ofthe U-shaped frame member 50 and the idler pulley 37 carried thereby.

In Figure 6 of the drawing, the casting machine is shown with theendless band removed and with the pouring ladle 21 in the extremeforward position. The pouring ladle 21 is pivotally mounted at 64 on thearm 57 which in turn is pivotally mounted about the hub 51 of thecasting drum 31. The pivotal position of the arm 57 is controlled bymeans of the handwheel 58. Rotation of the handwheel 58 causes arotation of the pinion gear 59 on the rack 60 which may be effective tomove the connecting link 61 to the right of the drawing as shown in Fig.6. Thus the pouring ladle 21 may be moved backwards to the operativeposition as shown in Fig. 2 of the drawings. A further adjustment of thetilt of the pouring ladle 21 is provided by means of the setscrews 62and 63 which adjust the pivotal position of the pouring ladle 21 aboutthe pivot point 64 on the end of the pivoted arm 57.

The guide member or roller 42 is clearly shown in Fig. 6 of the drawingsto be mounted on the free end of the lever arm 65 which is pivoted tothe base frame 32 of the machine and urged by the tension of the coilspring 43 to pivot towards the axis of the casting drum 31.

The upper guide member 41 is provided with a pivotal shoe member 67which is adapted to engage the inside surface of the endless band 36 asshown in Figs. 2 and 6 of the drawings. The shoe 67 may be channeled, asshown in Fig. 7 of the drawings, to receive a quantity of cotton wastewhich functions to clean the inside surface of the endless band 36 afterthe cast metal rod has been stripped from the casting groove and band.The shoe member 68, shown in Fig. 2 of the drawings, may also be adaptedto contain a quantity of cotton waste for cleaning the casting groove ofthe casting drum 31 after the cast metal has been stripped therefrom.

A detailed description of the heated metal pouring ladle 21 will now bedescribed in connection with Figs. 2, 4 and 5 of the drawings. Thepouring ladle 21 generally comprises an outer metal box structure 70aand an inner container 70. The bottom and side walls of the innercontainer 70 are spaced from the inner wall surfaces of the metal boxstructure 70a to provide passageways for the flow of burning gasesthereabout in a manner to heat the bottom and side wall-s of thecontainer 70. The burner 71 is adapted to project a flame of burninggases through the aperture 72 into the box 21 beneath the container 70.The pouring spout 30 extends from the bottom of the container 70 throughthe aperture 73 of the outer box of the ladle 21. It will be noted, asshown in Figure 2 of the drawings, that the aperture 73 is somewhatlarger than the external diameter of the pouring spout 30, so that theproducts of combustion from the burner 71 are exhausted through theaperture 73 around the external surfaces of the pouring spout 30. Insuch manner the pouring spout 30 is heated to prevent solidification, orpartial solidification, of metal in the spout which tends to accumulateafter long periods of continuous use. A transverse partition 74 extendsacross the path of movement of molten metal within the container 70 inits passage to the pouring spout 30. The opening 75, in the lowerportion of the transverse partition 74, permits the passage and flow ofmolten metal from the pouring ladle container 70 to the pouring spout30. Any scum or dross that is formed in the molten metal in thecontainer 70' and rises to the surface of the molten metal is preventedfrom entering the spout 30 since the spout is at the bottom of thecontainer. The opening 75 in the partition 74 is spaced above the bottomof the container and prevents the passage of heavy impurities which maycollect at the bottom of the container.

The cooling system for the rotatable casting drum is shown in detail inFigure 3 of the drawings. The rotatable casting drum 31 is provided withthe circular casting rim 78 which may be formed of copper or othersuitable highly heat conductive material. The rim 78 is secured to thedisc side wall 79 which is bolted to the rotatable axle sleeve 80. Theoutside disc side member 81 completes the assembly of the rotatablecasting drum to form a hollow enclosure adapted to contain a largevolume of cooling liquid 82. The rotatable axle sleeve 80 is mounted insuitable bearings 83 and 84 carried by the machine base frame 32. Asprocket 85 and chain 86 transmit rotation to the axle sleeve 80 fromthe power transmission contained in the base frame 32. The rotatableaxle sleeve 80 surrounds the stationary hub member or axle 88 having aconduit 89 drilled therethrough for the passage of cooling liquid intothe interior of the hollow casting drum 31. A nozzle 90 projects thecooling liquid from the intake conduit 89 into the central portion ofthe rotatable casting drum 31. A drain pipe 91 is also passed throughthe stationary hub portion 88 and is provided with an upwardly extendingend member 92 which extends virtually to the top of the interior of thecasting drum 31 to a point just beneath the inside perimeter of theperipheral casting rim 78. Thus substantially the entire enclosed volumeof the hollow casting drum may be continuously filled with a largemoving volume of cooling liquid. A thermo-couple 93 may be provided tomeasure the temperature of the cooling liquid as it is drained throughthe drainpipe 91 from the interior of the rotatable casting drum 31.

Additional refinements which contribute to the overall effectiveoperation of the continuous casting apparatus of the invention are shownin Fig. 2 of the drawings. The thermo-couple 94 may be provided tomeasure the temperature of the cast metal rod as it is stripped from thecasting machine. The thermocouple 95 may be provided to measure thetemperature of the cooling water contained in the pan 35 which surroundsthe lower external surfaces of the casting drum 31. The thermocouple 96may also be provided to measure the temperature of the molten metal inthe pouring ladle 21 before it is poured into the casting groove of thecasting drum.

A pressure roller 100 is carried by the adjustable guideway 101 andmovable to engage the exterior surface of the endless band 36 near thepoint of juncture of the band 36 with the peripheral surface ofrotatable casting drum 31. The control arm 102 is adapted to be rotatedto move the pressure roller 100 to or from the endless band 36 asdesired. It should be understood that the movement of the pressureroller 100 will vary the exact angle of contact of the endless band 36with the peripheral surface of the casting drum 31 at the point wherethe molten metal is poured into the casting groove.

As shown in Figure 3 of the drawings, the casting rim 78 is providedwith a casting groove having side walls 103 and 104 forming a castinggroove of generally triangular cross-section. If desired, the outeredges of the side walls 103 and 104 may be modified at 105 and 106 toextend substantially perpendicular to the periphery of the casting drumfor a short portion of their width. Such a modified form of castinggroove may further facilitate the continuous stripping of the cast metalrod from the casting groove in a manner to avoid excessive strains onthe cast metal rod.

The operationof the continuous metal casting apparatus of the inventionshould be readily apparent from the foregoing description and need notbe described in detail. It should be mentioned, however, when castingaluminum for example, that the machine may be operated to cast a speedof 10 to 30 feet per minute with an average weight of aluminum cast perhour of about 1,000 pounds. After the machine has been placed intooperation, the cast metal rod 40 is self-stripping. With the arrangementof continuous casting machine and metal melting furnaces as described,it is possible for a single operator to operate the machine and controlthe feed of molten metal thereto for long periods of time. Theflexibility of the entire arrangement is such that the important factorsfor controlling the quality of the cast metal rod may be easily takeninto consideration, and adjustments therefore may be made by a singlemachine operator. The cooling apparatus for the casting drum and theguide arrangements for the cast metal rod according to the invention,enable a uniformly high quality of continuously cast metal rod to beproduced. The particular heating arrangement for the metal pouring ladleas used on the continuous casting machine of the invention provides fora reliable continuous and uniformly controlled flow of molten metal tobe cast over long periods of time.

It should be understood that various modifications may be made withinthe spirit of the invention and scope of the appended claims.

We claim:

1. A rotatable casting drum for a machine for the continuous casting ofmolten metal into cast metal rod, said casting drum including incombination, a pair of disclike side walls disposed in spaced parallelrelation for rotation about a common horizontal axis and with one ofsaid side Walls having a central aperture therein, a circular castingrim of heat conductive material bridging respective peripheral portionsof said side Walls and afiixed thereto to form a hollow enclosureadapted to contain a cooling liquid, said casting rim having an externalcasting groove formed therein, a rotatable axle sleeve afiixed to saidone of said side walls and surrounding said central aperture therein,said sleeve extending coaxially with said horizontal axis of rotation ofsaid side walls, means for introducing a cooling liquid into saidenclosure through said sleeve, and a drain pipe extending through saidsleeve into said enclosure and having an end portion extending upwardlyin said enclosure to a point adjacent the internal surface of saidcasting rim so that substantially the entire enclosed volume of thecasting drum may be continuously filled with a large moving volume ofcooling liquid.

2. A rotatable casting drum for a machine for the continuous casting ofmolten metal into cast metal rod, said casting drum including incombination, a pair of disclike side walls disposed in spaced parallelrelation for rotation about a common horizontal axis and with one ofsaid side walls having a central aperture therein, a circular castingrim of heat conductive material bridging respective peripheral portionsof said side walls and affixed thereto to form a hollow enclosureadapted to contain a cooling liquid, said casting rim having an externalcasting groove formed therein, a rotatable axle sleeve affixed to saidone of said side walls and surrounding said central aperture therein,said sleeve extending coaxially with said horizontal axis of rotation ofsaid side walls, means for rotatably supporting said sleeve on saidhorizontal axis, driving means for imparting rotational motion to saidsleeve, means for introducing a cooling liquid into said enclosurethrough said sleeve, and a drain pipe extending through said sleeve intosaid enclosure and having an end portion extending upwardly in saidenclosure to a point adjacent the internal surface of said casting rimso that substantially the entire enclosed volume of the casting drum maybe continuously filled with a large moving volume of liquid.

(References on following page) References Cited in the file of thispatent UNITED STATES PATENTS Forsyth Apr. 24, 1883 Lane Dec. 28, 1926Walters Feb. 19, 1929 McMullan Mar. 17, 1931 Lindenberger Nov. 21, 1933Jacobson Sept. 24, 1935 Summey Nov. 10, 1936 Simons Aug. 29, 1939Junghans Oct. 15, 1940 Harter et a1. Oct. 9, 1951 FOREIGN PATENTS FranceIan. 17, 1951

1. A ROTATABLE CASTING DRUM FOR A MACHINE FOR THE CONTINUOUS CASTING OFMOLTEN METAL INTO CAST METAL ROD, SAID CASTING DRUM INCLUDING INCOMBINATION, A PAIR OF DISCLIKE SIDE WALLS DISPOSED IN SPACED PARALLELRELATION FOR ROTATION ABOUT A COMMON HORIZONTAL AXIS AND WITH ONE OFSAID SIDE WALLS HAVING A CENTRAL APERATURE THEREIN, A CIRCULAR CASTINGRIM OF HEAT CONDUCTIVE MATERIAL BRIDGING RESPECTIVE PERIPHERAL PORTIONSOF SAID SIDE WALLS AND AFFIXED THERETO TO FORM A HOLLOW ENCLOSUREADAPTED TO CONTAIN A COOLING LIQUID, SAID CASTING RIM HAVING AN EXTERNALCASTING GROOVE FORMED THEREIN, A ROTATABLE AXLE SLEEVE AFFIXED TO SAIDONE OF SAID SIDE WALLS AND SURROUNDING SAID CENTRAL APERTURE THEREIN,SAID SLEEVE EXTENDING COAXIALLY WITH SAID HORIZONTAL AXIS OF ROTATION OFSAID SIDE WALLS, MEANS FOR INTRODUCING A COOLING LIQUID INTO SAIDENCLOSURE THROUGH SAID SLEEVE, AND A DRAIN PIPE EXTENDING THROUGH SAIDSLEEVE INTO SAID ENCLOSURE AND HAVING AN END PORTION EXTENDING UPWARDLYIN SAID ENCLOSURE TO A POINT ADJACENT THE INTERNAL SURFACE OF SAIDCASTING RIM SO THAT SUBSTANTIALLY THE ENTIRE ENCLOSED VOLUME OF THECASTING DRUM MAY BE CONTINUOUSLY FILLED WITH A LARGE MOVING VOLUME OFCOOLING LIQUID.